Liquid agitator



March 28, 1944.

INVENTOR. JOSEPH R. LHTHHM BY iivmimm ATTDRNE YS March 28, 1944. J. R. LATHAM 2,345,130

LIQUID AGITATOR Filed Sept. 26, 1942 2 Sheets-Sheet 2 INVEN TOR. JOSEPH R. LA THEM Ba i 1m,

H TTORNE YS Patented Mar. 28, 1944 UNITED STATES PAT EN T ounce LIQUID. AGITATOR Joseph RoscoeiLatham, New Bern,"N. C. Application September 26," 1942, Serial l\l0.- 459,7 69

LGlaim.

invention relates toirnprovements in liquid agitators.

-An important object-of myinvention is'to profectively andefliciently mixing anyliquid or combination of liquids by a-thorough agitation thereof, such as is necessary at times to give I optimum results.

Another object thereof is -to provide a device ofthe classdescribe'd in whichliquidsmay be agitated at a'predetermin'ed speed and within a =predetermined'thne.

Another-object of myinvention is to "produce an agitator'particularly suitable-fer use'in clinical laboratories in the more efficient shaking and mixingof thereagentsused in making what is known as a Kahn test; now in use for the purpose of determining the presence or absence of syphilitic infection in human beings.

Other objects and advantages of my invention will either become apparent or be specifically referred to in connection with the following description thereof written in connection with the appended drawings, which illustrate a preferred embodiment thereof, and in which Figure 1 is an elevational view of my agitator with a portion broken away in order to show certain of its structural features.

Figure 2 is a sectional end view of the device taken on line 22 of Figure 1 and looking in the direction of the arrows, and

Figure 3 is a plan view of the device taken on line 33 of Figure 1 and looking in the direction of the arrows.

Referring particularly to the drawings, it will be seen that my device is preferably constructed in the for-m of a box In having a cover ll hinged thereto as at l2 and provided with any suitable lock or fastening means l3 such that by means of the handle l4, secured to the cover, the same is rendered portable, compact and sanitary. It will be understood however that other forms of a suitable frame or mounting therefor may b used.

Mounted within the box I is a rotatable horizontal shaft l5 having the ends thereof J'ournaled in bearings 16 secured in any suitable way to the inside surfaces of the ends l1l8 of said box [0. On the shaft l5, and preferably at points spaced equidistant from the journals 16, are provided any suitable form of crank means, which are here shown as a pair of eccentrics H! on each of which is rotatably mounted an eccentric strap or eye 20 integrally formed, respectively, on the ends of a pair of pitmans 2|. The ends of the pitmans 2 I, remote fromthe eyes '20,--are pivoted respectively, as at '22, to the lower endso'f a pair of depending 1inks23. The upper ends of the links 23 are pivoted, respectively, asrat 24, to

brackets 25, secured'in any suitable way to the inside surface of the'back of the' box 10.

'Referringnow'to Figure'2 it will be understood that when'theeccentrics I B are pos'itionedas plane'and employedassupports for a tan-k, tray or rack holder t!!! to which 'the same is secured -'by any suitable means, not shown. A suitable 'test tube holder of a sortmommonly sold and :used for the -purpose,-= or rack 231 provided with a plurality of holes 32, see Figure 3, and adapted to confine and support test tubes 33 in an upright position, is disposed within the tray 30. A retaining means, here shown in the form of spring means 34, is mounted in the tray 30 to grip releasably and retain the rack Si in place in said ray.

While any suitable variable speed motive means may be used for driving the shaft 15 and thereby impart to the tray 30 a compound motion of translation, tilting and rotation, as will be understood from the foregoing description of the structure of my agitator, I prefer to use, and have therefore illustrated here, an electric motor 35 mounted in the box It) having a suitable pulley 35 keyed to the armature shaft 31 thereof and adapted to drive the shaft l5 by means of a pulley 38, keyed thereto, and a belt 39 adapted to be driven by the pulley 36, as shown. To regulate the speed of the motor 35, a suitable rheostat 40 is mounted on the inside front wall of the box In and connected in series with the motor, as shown. The rheostat is provided with a controller knob 4| disposed on the outside thereof and by means of which the speed of the motor may be varied.

A plug socket 42 is connected in the motor circuit 43, as shown, and mounted on the back of the box l0 so that electric service connections may be made readily by means of an ordinary lamp cord assembly such as used extensively in connection with any well known household electric appliance.

At a certain stage in the performance of a Kahn test for the detection of syphilis referred to above, it is necessary to shake samples of blood with certain reagents in small test tubes for a certain number of minutes at a certain definite designated speed and in a certain manner. This was originally, and even today, largely done by technicians who placed the tubes in racks, like those illustrated and described here, and laboriously performed the agitating maneuver by hand.

In my device the tray 30, and therefore the liquid disposed therein, is given a compound motion, the component elements of which comprise the tilting or oscillation of the pitman 2| about the pivot 22 as the eccentric I9 is rotated by the shaft l andwhlile the end 22 of the pitman is permitted to move to and fro about the point 24 with a substantially rectilinear motion of translation. I prefer this construction because of its simplicity, although it will Ibe understood that the pivot 22 may also be mounted in any suitable horizontally disposed slot or raceway and similarly provide a suitable mounting for the same. The rotation of the eccentric I!) which tilts the pitman and tank 30 also rotates the forward end of the pitman with each revolution of the shaft I5. It will be seen therefore that my liquid container is mounted and supported on a pair of movable supports each adapted for a characteristically different movement.

In the device here shown the liquid to be agitated is preferably placed in the test tube to an elevation in the order of one-quarter inch and as a result of the operation of the motor there is imparted to the liquid a motion which I have described above as being of a compound nature resulting from movements, at any desirable speed, of translation, tilting and rotation. It will be understood, however, the liquids may be placed directly in the tank 30, and the same covered or not as desired, depending upon the size thereof and the quantity of liquid being agitated. When a tank or liquid container 30 of any suitable size and shape is provided with a close fitting cover, and suitably used in a device embodying my invention, I have discovered that the same is then admirably adapted for use as a washing machine for clothes, because of the nature of the gyrations which are imparted to the contents of such a container when the same is in motion.

While I have now described what seems to be a preferred embodiment of my invention it is conceivable that various modifications in the configuration, composition and disposition of the component elements making up the same as a whole, may occur to those skilled in the art as a result of my teachings here. Accordingly, no unnecessary limitation of my invention is intended by the phraseology of the foregoing description or the illustration of said preferred embodiment.

What I claim is:

A selective agitator for test tubes comprising a liquid container having means for supporting test tubes at various positions therein, a pair of movable means supporting said container adjacent opposite ends thereof, one of said supporting means being a pivot mounted for a simultaneous movement of translation and oscillation adjacent one end of the container and the other being a crank means mounted for a movement of retation and adjacent the other end of the container, in combination with means for rotating the crank means whereby one end of said container is moved .by said supporting means with a motion of translation principally and the other end with a motion of rotation principally.

JOSEPH ROSCOE LATHAM. 

